The invention is concerned with a method of screening patients for increased risk of breast cancer, by measuring the chloride concentration in breast cyst fluid aspirated from cysts in the patient's breast.
Carcinoma of the breast is one of the most common malignant tumors in women. It has been reported that over 4% of all women will develop cancer of the breast during their life. At least half of these will die of the condition and/or will suffer the trauma of a mutilating operation. Cystic or fibrocystic disease is the most common benign breast lesion occurring during the middle years of life. As cancer of the breast is the most common sex-specific entity occurring in the United States, a great deal of study has been centered upon the possible relationship of cystic disease of the breast to breast cancer. Different studies have reported some correlation e.g. Davis, "Cystic Disease of the Breast: Its Relationship to Mammary Carcinoma", pages 221-224 Progress in Clinical Cancer, 3; Veronesi et al, "Breast Cancer in Women Subsequent to Cystic Disease of the Breast, Surgery, Gynecology & Obstetrics 529-532 (March 1968); Harington, "The Association Between Gross Cyst of the Breast and Breast Cancer, Breast, Diseases of the Breast", Vol. 7, No. 1, pages 13-15 (1981)). However, these articles essentially concern the correlation of the existence of breast cysts with the risk of cancer. In general, of the numerous surveys which have been made of the incidence of breast cancer in patients suffering from cystic disease, the results broadly indicate that the incidence of breast cancer is 1.7 to 5 times higher than it is in the general female population. (Veronesi et al supra at page 530).
There are several studies which are reported in the text "Endocrinology of Cystic Breast Disease" Raven Press 1983, which discuss ions in breast cyst fluid. However, none of these articles correlate the presence of ions with the possibility of gross cystic disease.
The article by Bradlow et al entitled "Cations in Breast Cyst Fluids", reports breast cyst fluid cation concentrations but does not recognize the risk potential of ion concentration. The Gairard et al article entitled "Protein and Ionic Components in Breast Cyst Fluid" correlates electrolyte composition of breast cyst fluid with other components.